SyncMOS Technologies Inc.
SM5964
July 2002
Port4 (P4, $D8)
bit-7
Unused
*
bit-0
P4.0
1
Read :
Unused
*
Unused
*
Unused
*
P4.3
1
P4.2
1
P4.1
1
Write :
Reset value :
The bit 3, bit 2, bit 1, bit 0 output the setting to pin P4.3, P4.2, P4.1, P4.0 respectively.
3. In-System Programming (ISP) Function
The SM5964 can generate flash control signal by internal hardware circuit. User utilize flash control register, flash address
register and flash data register to perform the ISP function without removing the SM5964 from the system.
The SM5964 provides internal flash control signals which can do flash program/chip erase/page erase/protect functions.
User need to design and use any kind of interface which SM5964 can input data. User then utilize ISP service program to
perform the flash program/chip erase/page erase/protect functions.
3.1 ISP Service Program
The ISP service program is a user developed firmware program which resides in the ISP service program space. After
user developed the ISP service program, user then determine the size of the ISP service program. User need to program
the ISP service program in the SM5964 for the ISP purpose.
The ISP service program were developed by user so that it should includes any features which relates to the flash memory
programming function as well as communication protocol between SM5964 and host device which output data to the
SM5964. For example, if user utilize UART interface to receive/transmit data between SM5964 and host device, the ISP
service program should include baut rate, checksum or parity check or any error-checking mechanism to avoid data
transmission error.
The ISP service program can be initiated under SM5964 active or idle mode. It can not be initiated under power down
mode.
3.2. Lock Bit (N)
The Lock Bit N has two functions: one is for service program size configuration and the other is to lock the ISP service pro-
gram space from flash erase function.
The ISP service program space address range $F000 to $FFFF. It can be divided as blocks of N*512 byte. (N=0 to 8).
When N=0 means no ISP function, all of 64K byte flash memory can be used as program memory. When N=1 means ISP
service program occupies 512 byte while the rest of 63.5K byte flash memory can be used as program memory. The max-
imum ISP service program allowed is 4K byte when N=8. Under such configuration, the usable program memory space is
60K byte.
After N determined, SM5964 will reserve the ISP service program space downward from the top of the program address
$FFFF. The start address of the ISP service program located at $Fx00 while x is an even number, depending on the lock
bit N. Please see page 5 program memory diagram for this ISP service program space structure.
Specifications subject to change without notice,contact your sales representatives for the most recent information.
10/28
PID 5964 07/02
Ver 1.0
SYNCMOS [ SYNCMOS TECHNOLOGIES,INC ]
